Stir together sugar, spices, and salt and rub all over ribs to coat well, knocking off excess.
Put chips in foil and crimp tightly closed to form a packet. Poke holes all over packet.
Stir together all sauce ingredients until sugar is dissolved.
Open vents two-thirds in lid and bottom of grill. Light half a chimney of charcoal, then put on one side of bottom rack, mounding and banking against side. Charcoal will be ready for cooking when it turns grayish white (10 to 15 minutes). Temperature should be about 350 degrees F inside covered grill. Add additional charcoal if necessary. (Temperature will gradually drop during cooking; the goal is to maintain a low, continuous heat, about 250 degrees F.) Put wood-chip packet on coals, then arrange grill rack so that one hinged side is over the coals.
Oil rack lightly. Arrange ribs on rack so that they do not extend over coals, then cover.
Cook ribs, covered until tender, about 4 hours. Every 20 minutes, baste ribs with sauce, turn over and switch positions, and add about 8 pieces of charcoal to the mound.